(1) Field of the Invention
Various flat plane holding devices are in use today for positioning electronic circuit boards, parts to be machined, pictures, photographic film and the like. However, conventional devices do not have the ability to accurately center variously sized planes or to determine the orientation of the plane whether it be upon a longitudinal or a transverse axis.
(2) Description of the Prior Art
Barton: u.s. pat. No. 3,888,476 PA0 Day: u.s. pat. No. 3,590,458 PA0 Madsen: u.s. pat. No. 1,612,299 PA0 Bergstrom: u.s. pat. No. 1,342,891 PA0 Duus: u.s. pat. No. 1,000,725 PA0 Lawson: u.s. pat. No. 840,777 PA0 Jacobs: u.s. pat. No. 744,555 PA0 Reissmann: u.s. pat. No. 604,160
The foregoing patents teach various clamp means for positioning of articles with respect to cameras, machine devices and the like. However, none of them suggest means for automatically centering congruent rectangles or indicating relative orientation either upon a longitudinal or transverse axis. The prior devices broadly illustrate using two pairs of diagonal clamping devices positionable against variously sized rectangular pieces. However, there is no suggestion of employing a single pair of clamps and associated circuitry for sensing both the size and orientation of variously sized rectangles. Furthermore, the prior art does not suggest the employment of a single arcuate slot for permitting travel of the clamping devices along separate linear paths of orientation.
The patent to Barton is merely of interest for an articulated arm arrangement useful for symmetrically mounting and clamping variously angled corners within a frame structure.
The patent to Day shows a holding fixture wherein four pivoted arms respectively carry right angle corner clamps which are manually slideable movement along each arm. Any centering of a frame with the device of Day requires careful manual adjustment of all runners to ensure that the respective sides of a frame properly define a rectangular assembly.
The manual clamping device of Madsen similarly provides for rotating arms with diagonal opposite clamping elements being moved equal amounts, relative to the center, through operation of a single hand crank. However, the diagonal clamp of Madsen has no provision for sensing orientation of a held rectangular piece. Nor does Madsen provide for a pair of guide slots, operable for selectively positioning the locus of travel for diagonal holders along a line A, or a second line B.
The early patent to Bergstrom teaches a clamp for repeatedly clamping one given size of a frame through the provision of a treadle, and associated chain, for simultaneously urging four miter clamps inwardly.
The patent to Duus illustrates a miter clamping assembly which includes, at FIG. 6, a series of rack and pinion devices for adjusting the size of the frame to be clamped. However, again all four clamps are articulated together and there is no provision for an automatic clamping which develops an orientation output signal.
The clamp of Lawson is another articulated holding fixture which provides for clamping mitered corners through a single adjustment. Again, Lawson is without structural or functional similarity to your client's automatic positioning device.
The clamp of Jacobs is analogous to the prior-art type of clamp conventionally used to hold X-ray cassettes. In Jacobs there is no provision for centering congruently sized rectangles with respect to a mid-point on the holding fixture.
Finally, the very early patent to Reissmann illustrates another form of miter clamp wherein four holding fixtures are mutually rotated through a single crank handle by an associated central gear assembly.